netfilter: xtables: change hotdrop pointer to direct modification

Since xt_action_param is writable, let's use it. The pointer to
'bool hotdrop' always worried (8 bytes (64-bit) to write 1 byte!).
Surprisingly results in a reduction in size:

   text    data     bss filename
5457066  692730  357892 vmlinux.o-prev
5456554  692730  357892 vmlinux.o

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

21 files changed, 43 insertions, 46 deletions

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 290d43541d46..59ca00e40dec 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -186,13 +186,12 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb,
         struct ebt_entries *chaininfo;
         const char *base;
         const struct ebt_table_info *private;
-        bool hotdrop = false;
         struct xt_action_param acpar;
 
         acpar.family  = NFPROTO_BRIDGE;
         acpar.in      = in;
         acpar.out     = out;
-        acpar.hotdrop = &hotdrop;
+        acpar.hotdrop = false;
         acpar.hooknum = hook;
 
         read_lock_bh(&table->lock);
@@ -216,7 +215,7 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb,
 
                 if (EBT_MATCH_ITERATE(point, ebt_do_match, skb, &acpar) != 0)
                         goto letscontinue;
-                if (hotdrop) {
+                if (acpar.hotdrop) {
                         read_unlock_bh(&table->lock);
                         return NF_DROP;
                 }
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 9e7d089f168a..8cc56d26e937 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -260,7 +260,6 @@ unsigned int arpt_do_table(struct sk_buff *skb,
         static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
         unsigned int verdict = NF_DROP;
         const struct arphdr *arp;
-        bool hotdrop = false;
         struct arpt_entry *e, *back;
         const char *indev, *outdev;
         void *table_base;
@@ -284,6 +283,7 @@ unsigned int arpt_do_table(struct sk_buff *skb,
         acpar.out     = out;
         acpar.hooknum = hook;
         acpar.family  = NFPROTO_ARP;
+        acpar.hotdrop = false;
 
         arp = arp_hdr(skb);
         do {
@@ -345,10 +345,10 @@ unsigned int arpt_do_table(struct sk_buff *skb,
                 else
                         /* Verdict */
                         break;
-        } while (!hotdrop);
+        } while (!acpar.hotdrop);
         xt_info_rdunlock_bh();
 
-        if (hotdrop)
+        if (acpar.hotdrop)
                 return NF_DROP;
         else
                 return verdict;
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 4e674f2824a7..607f89f16b76 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -308,7 +308,6 @@ ipt_do_table(struct sk_buff *skb,
 {
         static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
         const struct iphdr *ip;
-        bool hotdrop = false;
         /* Initializing verdict to NF_DROP keeps gcc happy. */
         unsigned int verdict = NF_DROP;
         const char *indev, *outdev;
@@ -330,7 +329,7 @@ ipt_do_table(struct sk_buff *skb,
          * match it. */
         acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
         acpar.thoff   = ip_hdrlen(skb);
-        acpar.hotdrop = &hotdrop;
+        acpar.hotdrop = false;
         acpar.in      = in;
         acpar.out     = out;
         acpar.family  = NFPROTO_IPV4;
@@ -432,7 +431,7 @@ ipt_do_table(struct sk_buff *skb,
                 else
                         /* Verdict */
                         break;
-        } while (!hotdrop);
+        } while (!acpar.hotdrop);
         xt_info_rdunlock_bh();
         pr_debug("Exiting %s; resetting sp from %u to %u\n",
                  __func__, *stackptr, origptr);
@@ -440,7 +439,7 @@ ipt_do_table(struct sk_buff *skb,
 #ifdef DEBUG_ALLOW_ALL
         return NF_ACCEPT;
 #else
-        if (hotdrop)
+        if (acpar.hotdrop)
                 return NF_DROP;
         else return verdict;
 #endif
@@ -2154,7 +2153,7 @@ icmp_match(const struct sk_buff *skb, struct xt_action_param *par)
                  * can't.  Hence, no choice but to drop.
                  */
                 duprintf("Dropping evil ICMP tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv4/netfilter/ipt_ah.c b/net/ipv4/netfilter/ipt_ah.c
index c9d83dc2d6fa..14a2aa8b8a14 100644
--- a/net/ipv4/netfilter/ipt_ah.c
+++ b/net/ipv4/netfilter/ipt_ah.c
@@ -46,7 +46,7 @@ static bool ah_mt(const struct sk_buff *skb, struct xt_action_param *par)
                  * can't.  Hence, no choice but to drop.
                  */
                 pr_debug("Dropping evil AH tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return 0;
         }
 
diff --git a/net/ipv4/netfilter/ipt_ecn.c b/net/ipv4/netfilter/ipt_ecn.c
index b79dddc9edd6..af6e9c778345 100644
--- a/net/ipv4/netfilter/ipt_ecn.c
+++ b/net/ipv4/netfilter/ipt_ecn.c
@@ -78,7 +78,7 @@ static bool ecn_mt(const struct sk_buff *skb, struct xt_action_param *par)
         if (info->operation & (IPT_ECN_OP_MATCH_ECE|IPT_ECN_OP_MATCH_CWR)) {
                 if (ip_hdr(skb)->protocol != IPPROTO_TCP)
                         return false;
-                if (!match_tcp(skb, info, par->hotdrop))
+                if (!match_tcp(skb, info, &par->hotdrop))
                         return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 4549f8d6f88f..557fac9689c0 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -337,7 +337,6 @@ ip6t_do_table(struct sk_buff *skb,
               struct xt_table *table)
 {
         static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
-        bool hotdrop = false;
         /* Initializing verdict to NF_DROP keeps gcc happy. */
         unsigned int verdict = NF_DROP;
         const char *indev, *outdev;
@@ -356,7 +355,7 @@ ip6t_do_table(struct sk_buff *skb,
          * things we don't know, ie. tcp syn flag or ports).  If the
          * rule is also a fragment-specific rule, non-fragments won't
          * match it. */
-        acpar.hotdrop = &hotdrop;
+        acpar.hotdrop = false;
         acpar.in      = in;
         acpar.out     = out;
         acpar.family  = NFPROTO_IPV6;
@@ -380,7 +379,7 @@ ip6t_do_table(struct sk_buff *skb,
 
                 IP_NF_ASSERT(e);
                 if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
-                    &acpar.thoff, &acpar.fragoff, &hotdrop)) {
+                    &acpar.thoff, &acpar.fragoff, &acpar.hotdrop)) {
  no_match:
                         e = ip6t_next_entry(e);
                         continue;
@@ -447,7 +446,7 @@ ip6t_do_table(struct sk_buff *skb,
                 else
                         /* Verdict */
                         break;
-        } while (!hotdrop);
+        } while (!acpar.hotdrop);
 
         xt_info_rdunlock_bh();
         *stackptr = origptr;
@@ -455,7 +454,7 @@ ip6t_do_table(struct sk_buff *skb,
 #ifdef DEBUG_ALLOW_ALL
         return NF_ACCEPT;
 #else
-        if (hotdrop)
+        if (acpar.hotdrop)
                 return NF_DROP;
         else return verdict;
 #endif
@@ -2170,7 +2169,7 @@ icmp6_match(const struct sk_buff *skb, struct xt_action_param *par)
                  * can't.  Hence, no choice but to drop.
                  */
                 duprintf("Dropping evil ICMP tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_ah.c b/net/ipv6/netfilter/ip6t_ah.c
index c89887f35a46..89cccc5a9c92 100644
--- a/net/ipv6/netfilter/ip6t_ah.c
+++ b/net/ipv6/netfilter/ip6t_ah.c
@@ -48,13 +48,13 @@ static bool ah_mt6(const struct sk_buff *skb, struct xt_action_param *par)
         err = ipv6_find_hdr(skb, &ptr, NEXTHDR_AUTH, NULL);
         if (err < 0) {
                 if (err != -ENOENT)
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 return false;
         }
 
         ah = skb_header_pointer(skb, ptr, sizeof(_ah), &_ah);
         if (ah == NULL) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_eui64.c b/net/ipv6/netfilter/ip6t_eui64.c
index f32fce34145a..aab0706908c5 100644
--- a/net/ipv6/netfilter/ip6t_eui64.c
+++ b/net/ipv6/netfilter/ip6t_eui64.c
@@ -27,7 +27,7 @@ eui64_mt6(const struct sk_buff *skb, struct xt_action_param *par)
         if (!(skb_mac_header(skb) >= skb->head &&
               skb_mac_header(skb) + ETH_HLEN <= skb->data) &&
             par->fragoff != 0) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_frag.c b/net/ipv6/netfilter/ip6t_frag.c
index fcc8c72f218e..eda898fda6ca 100644
--- a/net/ipv6/netfilter/ip6t_frag.c
+++ b/net/ipv6/netfilter/ip6t_frag.c
@@ -46,13 +46,13 @@ frag_mt6(const struct sk_buff *skb, struct xt_action_param *par)
         err = ipv6_find_hdr(skb, &ptr, NEXTHDR_FRAGMENT, NULL);
         if (err < 0) {
                 if (err != -ENOENT)
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 return false;
         }
 
         fh = skb_header_pointer(skb, ptr, sizeof(_frag), &_frag);
         if (fh == NULL) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_hbh.c b/net/ipv6/netfilter/ip6t_hbh.c
index f8aebc098d71..59df051eaef6 100644
--- a/net/ipv6/netfilter/ip6t_hbh.c
+++ b/net/ipv6/netfilter/ip6t_hbh.c
@@ -65,13 +65,13 @@ hbh_mt6(const struct sk_buff *skb, struct xt_action_param *par)
                             NEXTHDR_HOP : NEXTHDR_DEST, NULL);
         if (err < 0) {
                 if (err != -ENOENT)
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 return false;
         }
 
         oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh);
         if (oh == NULL) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_mh.c b/net/ipv6/netfilter/ip6t_mh.c
index eb1c3d65271a..0c90c66b1992 100644
--- a/net/ipv6/netfilter/ip6t_mh.c
+++ b/net/ipv6/netfilter/ip6t_mh.c
@@ -47,14 +47,14 @@ static bool mh_mt6(const struct sk_buff *skb, struct xt_action_param *par)
                 /* We've been asked to examine this packet, and we
                    can't.  Hence, no choice but to drop. */
                 pr_debug("Dropping evil MH tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
         if (mh->ip6mh_proto != IPPROTO_NONE) {
                 pr_debug("Dropping invalid MH Payload Proto: %u\n",
                          mh->ip6mh_proto);
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/ipv6/netfilter/ip6t_rt.c b/net/ipv6/netfilter/ip6t_rt.c
index ee584693ee35..d8488c50a8e0 100644
--- a/net/ipv6/netfilter/ip6t_rt.c
+++ b/net/ipv6/netfilter/ip6t_rt.c
@@ -52,13 +52,13 @@ static bool rt_mt6(const struct sk_buff *skb, struct xt_action_param *par)
         err = ipv6_find_hdr(skb, &ptr, NEXTHDR_ROUTING, NULL);
         if (err < 0) {
                 if (err != -ENOENT)
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 return false;
         }
 
         rh = skb_header_pointer(skb, ptr, sizeof(_route), &_route);
         if (rh == NULL) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c
index f130fd9817be..5c5b6b921b84 100644
--- a/net/netfilter/xt_connlimit.c
+++ b/net/netfilter/xt_connlimit.c
@@ -206,14 +206,14 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
 
         if (connections < 0) {
                 /* kmalloc failed, drop it entirely */
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
         return (connections > info->limit) ^ info->inverse;
 
  hotdrop:
-        *par->hotdrop = true;
+        par->hotdrop = true;
         return false;
 }
 
diff --git a/net/netfilter/xt_dccp.c b/net/netfilter/xt_dccp.c
index cc2c2919439f..b63d2a3d80ba 100644
--- a/net/netfilter/xt_dccp.c
+++ b/net/netfilter/xt_dccp.c
@@ -107,7 +107,7 @@ dccp_mt(const struct sk_buff *skb, struct xt_action_param *par)
 
         dh = skb_header_pointer(skb, par->thoff, sizeof(_dh), &_dh);
         if (dh == NULL) {
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
@@ -120,7 +120,7 @@ dccp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                 && DCCHECK(match_types(dh, info->typemask),
                            XT_DCCP_TYPE, info->flags, info->invflags)
                 && DCCHECK(match_option(info->option, skb, par->thoff, dh,
-                                        par->hotdrop),
+                                        &par->hotdrop),
                            XT_DCCP_OPTION, info->flags, info->invflags);
 }
 
diff --git a/net/netfilter/xt_esp.c b/net/netfilter/xt_esp.c
index 7c2d80020554..171ba82b5902 100644
--- a/net/netfilter/xt_esp.c
+++ b/net/netfilter/xt_esp.c
@@ -52,7 +52,7 @@ static bool esp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                  * can't.  Hence, no choice but to drop.
                  */
                 pr_debug("Dropping evil ESP tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c
index 25a6e548ec27..b46a8390896d 100644
--- a/net/netfilter/xt_hashlimit.c
+++ b/net/netfilter/xt_hashlimit.c
@@ -562,7 +562,7 @@ hashlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
         return info->cfg.mode & XT_HASHLIMIT_INVERT;
 
  hotdrop:
-        *par->hotdrop = true;
+        par->hotdrop = true;
         return false;
 }
 
diff --git a/net/netfilter/xt_multiport.c b/net/netfilter/xt_multiport.c
index 52beb68256c8..ac1d3c3d09e7 100644
--- a/net/netfilter/xt_multiport.c
+++ b/net/netfilter/xt_multiport.c
@@ -87,7 +87,7 @@ multiport_mt(const struct sk_buff *skb, struct xt_action_param *par)
                  * can't.  Hence, no choice but to drop.
                  */
                 pr_debug("Dropping evil offset=0 tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index 2808a7e33947..76aec6a44762 100644
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -268,7 +268,7 @@ recent_mt(const struct sk_buff *skb, struct xt_action_param *par)
                         goto out;
                 e = recent_entry_init(t, &addr, par->family, ttl);
                 if (e == NULL)
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 ret = !ret;
                 goto out;
         }
diff --git a/net/netfilter/xt_sctp.c b/net/netfilter/xt_sctp.c
index 94d8b5deb2d0..c04fcf385c59 100644
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -128,7 +128,7 @@ sctp_mt(const struct sk_buff *skb, struct xt_action_param *par)
         sh = skb_header_pointer(skb, par->thoff, sizeof(_sh), &_sh);
         if (sh == NULL) {
                 pr_debug("Dropping evil TCP offset=0 tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
         pr_debug("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest));
@@ -140,7 +140,7 @@ sctp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                         && ntohs(sh->dest) <= info->dpts[1],
                         XT_SCTP_DEST_PORTS, info->flags, info->invflags)
                 && SCCHECK(match_packet(skb, par->thoff + sizeof(sctp_sctphdr_t),
-                                        info, par->hotdrop),
+                                        info, &par->hotdrop),
                            XT_SCTP_CHUNK_TYPES, info->flags, info->invflags);
 }
 
diff --git a/net/netfilter/xt_tcpmss.c b/net/netfilter/xt_tcpmss.c
index f90728f6b8a4..c53d4d18eadf 100644
--- a/net/netfilter/xt_tcpmss.c
+++ b/net/netfilter/xt_tcpmss.c
@@ -73,7 +73,7 @@ out:
         return info->invert;
 
 dropit:
-        *par->hotdrop = true;
+        par->hotdrop = true;
         return false;
 }
 
diff --git a/net/netfilter/xt_tcpudp.c b/net/netfilter/xt_tcpudp.c
index dedde33c9db6..c14d4645daa3 100644
--- a/net/netfilter/xt_tcpudp.c
+++ b/net/netfilter/xt_tcpudp.c
@@ -77,7 +77,7 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                 */
                 if (par->fragoff == 1) {
                         pr_debug("Dropping evil TCP offset=1 frag.\n");
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                 }
                 /* Must not be a fragment. */
                 return false;
@@ -90,7 +90,7 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                 /* We've been asked to examine this packet, and we
                    can't.  Hence, no choice but to drop. */
                 pr_debug("Dropping evil TCP offset=0 tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }
 
@@ -108,13 +108,13 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                 return false;
         if (tcpinfo->option) {
                 if (th->doff * 4 < sizeof(_tcph)) {
-                        *par->hotdrop = true;
+                        par->hotdrop = true;
                         return false;
                 }
                 if (!tcp_find_option(tcpinfo->option, skb, par->thoff,
                                      th->doff*4 - sizeof(_tcph),
                                      tcpinfo->invflags & XT_TCP_INV_OPTION,
-                                     par->hotdrop))
+                                     &par->hotdrop))
                         return false;
         }
         return true;
@@ -143,7 +143,7 @@ static bool udp_mt(const struct sk_buff *skb, struct xt_action_param *par)
                 /* We've been asked to examine this packet, and we
                    can't.  Hence, no choice but to drop. */
                 pr_debug("Dropping evil UDP tinygram.\n");
-                *par->hotdrop = true;
+                par->hotdrop = true;
                 return false;
         }